The model is already showing as "Discontinued" in most OnePlus online stores across Europe, Asia and North America with the exception of the UK where the Gunmetal version of the model is still showing in stock. It is likely to be removed from there too, soon.

In a Reddit thread, a OnePlus representative confirmed the discontinuation saying the company was looking to focus its efforts on one just "one flagship device ". He was likely hinting at the OnePlus 5 which is rumoured to launch sometime this summer.

Tech website Tweakers, however, says the discontinuation may not be linked to the OnePlus 5 launch directly. The UFS storage used in the 128 GB model, the UFS 2.0, is apparently no longer being supplied by Samsung. The next generation UFS storage, which is UFS 2.1, is likely to be reserved for the company's next model, the OnePlus 5.

For now, the 64GB of the OnePlus 3T is still available in all OnePlus stores. If you think you may have missed out on the OnePlus 3T 128GB version, you can still try some third-party sellers who may be keeping the model in stock.

If you still cherish a OnePlus phone but do not fancy a 64GB model, wait till the summer for the OnePlus 5. The upcoming OnePlus 5 is rumoured to come with a 5.5in screen with 2K resolution running on Qualcomm's Snapdragon 835 chip and possessing 8GB of RAM. It will likely feature a dual-lens 23 megapixel camera with optical image stabilisation and a 3,000mAh battery.